Unfortunately, with a three-year old who picks up the phone every chance he gets, I ended up giving up on the no-case thing and started a hunt a weekend ago. Thankfully, Toshi is available.with their universal cases and they have a lot of cute designs so I picked one that makes me yearn for Disneyland.
It fits anything in the range it's meant for but with my slim phone (Xperia C3), the case feels like it was meant for a bulkier phone. My one peeve is that I can't take pictures from the back like I used to be able to. On a last note, it's pretty so I got what I wanted, and that's what matters to me.